Have you check out Bigpumpkins.com you can go in to the chat section and ask qusetions about growing big pumpkins?

Melissa

Andrew, First let me say that there is no one single best way to grow big pumpkins, and that applies to both of your questions. Some very good growers start the seeds indoors for varying lengths of time ahead of the normal planting time. Other very good growers maintain that merely transplanting the growing seeds sets them back. So, as you see, it all depends upon who you ask.
As for the fertilizer question, it is sort or the same thing - each individual seems to have his own schedule of when to apply different fertilizer formulae, how often or if at all to use foliar spray, etc. The best advice is probably to prepare your soil the Fall before you plant, including lime, fertilizer and minerals, and often using a good cover crop. You might also consider the addition of organic material and/or something granular (sand, perlite, etc) to condition the soil. When I was younger I used to bury a fish about a foot or so beneath certain seeds, and I raised some truly giant sunflowers back in the 1960's, before this sort of thing became so popular and competitive. And by a fish I'm talkinmg a ten to twelve pound carp, not a two ounce bluegill. I tried this three years ago when planting a little fig tree, and the results were spectacular. However, I no longer do much fishing, so no fish.
If you use the search engine, on this forum, for fertilizing pumpkins, you are likely to come up with some prior postings which could be of value. But, please remember that what might work in Nova Scotia might not work in California.....Elder